An increasing number of proteins, including enzymes, are being produced industrially, for use in various industries, housekeeping and medicine. Being proteins they are likely to stimulate an immunological response in man and animals, e.g. an allergic response.
Various attempts to alter the immunogenicity of proteins have been conducted. In general it is only localized parts of the protein, known as epitopes, which are responsible for induction of an immunologic response. An epitope consist of a number of amino acids, which may in the primary sequence be sequential but which more often are located in proximity of each other in the 3-dimensional structure of the protein. It has been found that small changes in an epitope may affect the binding to an antibody. This may result in a reduced importance of such an epitope, maybe converting it from a high affinity to a low affinity epitope, or maybe even result in epitope loss, i.e. that the epitope cannot sufficiently bind an antibody to elicit an immunogenic response.
Another method for altering the immunogenicity of a protein is by masking the epitopes by e.g. adding compounds, such as PEG, to the protein.
WO 00/26230 and WO 01/83559 disclose two different methods of selecting a protein variant having reduced immunogenicity as compared to the parent protein.
WO 99/38978 discloses a method for modifying allergens to be less allergenic by modifying the IgE binding sites.
WO 99/53038 discloses mutant proteins having lower allergenic response in humans and methods for constructing, identifying and producing such proteins.
Subtilases, which have a wide-spread use within the detergent industry, is a group of enzymes which potentially may elicit an immunogenic response, such as allergy. Thus there is a constant need for subtilases or subtilase variants which have an altered immunogenicity, particularly a reduced allergenicity and which at the same still maintain the enzymatic activity necessary for their application.
WO 00/22103 discloses polypeptides with reduced immune response and WO 01/83559 discloses protein variants having modified immunogenicity.